Apparatus for perforation of cinematographic films



.Lf-G. W. mmm APPARATUS, Foa PEx-zFoHATa-us; uF'lcmEMAToGRAPHm mms.

` MFLICATION FILED SEPT. 18, 1,919.

'Emma May 24, 1921-.

UNITED sTATss rTsNT oFFIcE.

DENMARK.

APPARATUS FOR PERFORATION 0F CINEMATOGRAPI-IIC FILMS.

Speccation of Letters Patent.

Patented May 24, 1921.

Application ined september 1s, 191e. serial No. 324,641.

T 0 all whom t may concern Be it known that I, ERNST GUs'rAv WIL- HELMDiaframma subject of the King ofV Denmark, residing at Charlottenlund,near Copenhagen, Denmark, have invented new and useful ImprovementsinAppa-ratus for Perforation of Cinematographic Films, of which thefollowing is a specification.

In the previous used apparatuses for perforating of cinematographicfilms, a socalled catcher is used for feeding the film forward duringthe punching operation. The catcher consists mainly of areciproeatingarm fitted with pins or claws which are inserted into the holes punchedin the film, and feed the film forward a distance equal to thespacing-or a multiple of the spacingof the holes for each back and forthstroke of the catcher. In order to prevent any error present in thespacing of the holes from accumulating, it is necessary that the clawsof the catcher, whenever they engage the holes Vpunched in the film,should be inserted into the last hole or holes punched. Apparatuseswhere this is done have been constructed, but they are suhj ect to thedrawback that the apparatus cannot operate at a sufficiently high speed,because theperforating punch as well as the die must be movedconsiderably away from the lm, in order that the catcher may operatefreely.

This drawback has been avoided by letting the catcher work at somedistance from the place where the perforation is performed, there beingthen used two or more guiding pins in firm connection with the punch.The catcher would then feed the film forward some distance, whereafterthe guiding pins (whose distance from the punch was exactly onehole-space, and whose front and rear sides, in the direction of themoving film, were beveled,) would be inserted into the holes lastpunched, so that either one or the other of the beveled faces of theguiding` pins would force the film into exact position, y

the sum of the motions received by the film from the catcher and theguiding pins 'equaling exactly one hole-space. In the beginning, therewill hereby be attained an eX- ceedingly accurate adjustment of theholespacing, but the apparatus is subject to the drawback that theguiding pins will quickly be worn and cause the perforation to beinaccurate. Besides, the guiding pins in such apparatus are notadjustable.

These drawbacks are avoided entirely, according to the presentinvention, in thaty instead of theregular catcher there is used one ormore Vguiding pins 4adjustably connected to the punch or punches, whichpunch and consequently the guidingl pins thereon are given a circularmotion relatively to the fixed portion of the apparatus. The circular4movement may be truly circular, elliptical, or other endless movement.During a portion of this motion, the punch will cut a hole in the'film,while the guiding pin takes care 0f the` entire motion of the film,pushing the latter forward partly hefore and during7 and partly after,punching, so that the total motion of the film between two consecutivepunchings of holes becomes er;- actly equal to one hole-space.

The drawing shows one manner of constructing the invention,

The figure showing a perforating apparatus in side elevation.

l is a fixed bearing or frame, wherein a shaft 2 is journaled. Thisshaft is fitted with an eccentricdisk 8, which moves a connecting rod4;, when the shaft 2 revolves, the said connecting rod imparting,thereby, a reciproca-ting motion yt0 a carriage 5. The perforating punch6 is fastened in a head "7 rmly connected tothe end of the connectingrod 4 actuated by the disk 3. 8 is the die, which is seated on thecarriage 5 directly below the punch 6. One end of the connecting rod 4lis connected to the carriage 5 and imparts thereto a rectilinearreciprocating motion. The head 7 carrying the punch (i and pin 9 willbe'given an elliptic motion, as indicated by dotted lines in F ig. l.

10 is a stationary table, whereon the film 1i slides' in the directionindicated by the arrow P1, while the perforation is being performed. Theside of the guiding pin facing the punch is obliquely cut as shown. l2is a fiywheel disposed on the shaft 2.

cornNnAGnN, f

The apparatus acts in the following man- 10 moves downward, and vthisdownward mothe revolution of the eccentric 3, the punch is again movedupward and away from the film. After the punch 6 has been withdrawn fromthe film, the guiding pin 9 will remain, for" a short while, inengagement with the said hole, coperating with the front edge Y thereofduring the 'last portion of the rotation of the eccentric 3 and,thereby, impart to the film a final relatively short forward motionsmaller than one hole-space. This space and the accuracy of the motionmay be adjusted by vertical adjustment of the guiding pin, the latterthen engaging the film during a shorter or longer time, depending on theadjustment, after the punch has been withdrawn from the film and,thereby, moving the film forward a shorter or longer distance. Thehole-spacing may also be adjusted morercoarsely byselection of suitabledifferent eccentrics y3. For effecting the vertical adjustment of thepin 9 in the head 7, a set screw 9 may be provided.

The film slides on the table 10 and is guided thereon by the table beingfitted with raised side edges. The lm forms4 a loop on the supply sideof the apparatus as well as on `'the discharge side thereof. Hereby anadvantage is attained in that nothing opposes the displacements of thefilm due to the action of the punch and the guiding pin; Y

The perforation ofthe two rows of holes in the same film isperformedsimultaneously by means of-two punches, which may be fastened in one andthe same punch holder. In this case, there may be used a single guidingpin in connection with one'of the punches or if desired, a series of oneor more guiding pins for each of the punches. A.

Vsaid guide-pin and punch are mounted, and

means for imparting circular movement to said head 'carrying said punchand guidepin so as to cause said punch and guide-pin tizio bothperforateand by steps advance the 2. In an apparatus for perforatingfilms thecombination of apunch, a die, a guidepin for advancing the film, a headon which said guide-pin andpunch are mounted, and means for impartingcircular movement to said head carrying said punchvv vand saidguide-pin, so as to cause said punch to perforate the film, and saidVguide pin to by steps advance the film exclusively by means ofsaidguide-pin. f

3. In an apparatus for perforating lms the combination of a'punch, adie, a guidepin for advancing thefilm, a head on which said guide-pinand punch are mounted, and means forimparting circular movement tosaidhead carrying said punch and said guide-pin, and a reciprocatingmovement to said die, so as to cause said punch to perforate the film,vand said guide-pin to by steps advance the film lexclusively by meansof said guide-pin. v

1l. In an apparatus forvperforating films the combination of a punch, adie, a guidepin for advancing the film, a head on which said guide-pinandv punch are mounted, said guidepin being adjustable, andmeans forimparting circular movement to said head carrying said punch and saidguide-pin, and a reciprocating movement to said die, so as to cause saidpunch to perforate the film, and'said guide-pin to by steps advance thefilm exclusivelyY by means of said guidepm. Y

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

ERNST GUSTAV WILHELM DITTMER.

